256507172605425 has 24 divisors (see below), whose sum is σ = 484676409952576. Its totient is φ = 117260421762240.

The previous prime is 256507172605423. The next prime is 256507172605447. The reversal of 256507172605425 is 524506271705652.

It is not a de Polignac number, because 256507172605425 - 2¹ = 256507172605423 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256507172605423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 244292544814 + ... + 244292545863.

Almost surely, 2^{256507172605425} is an apocalyptic number.

256507172605425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

256507172605425 is a deficient number, since it is larger than the sum of its proper divisors (228169237347151).

256507172605425 is a wasteful number, since it uses less digits than its factorization.

256507172605425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 488585090697 (or 488585090692 counting only the distinct ones).

The product of its (nonzero) digits is 35280000, while the sum is 57.

The spelling of 256507172605425 in words is "two hundred fifty-six trillion, five hundred seven billion, one hundred seventy-two million, six hundred five thousand, four hundred twenty-five".